Key blank identification system with bitting analysis

ABSTRACT

A key identification system is provided. The key identification system comprises a sensing device configured to extract bitting information from a master key, and a logic configured to analyze the image. The sensing device may be configured to capture information about the bittings of the master key, such as an image of the bittings. The logic analyzes information about the bittings of the master key and compares it with bitting characteristics of known key blanks to determine the likelihood of a match between the master key and a known key blank.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority of U.S. ProvisionalPatent Application Ser. No. 61/215,122 filed on May 1, 2009, and U.S.Provisional Patent Application Ser. No. 61/275,648 filed on Sep. 1,2009, each of which are hereby incorporated by reference in theirentirety.

FIELD OF ART

This invention relates generally to the field of systems for identifyingobjects and, more particularly to systems for utilizing a means foridentifying key blanks that are functionally compatible with an unknownkey.

BACKGROUND OF THE INVENTION

The art of key replication is well known. Commonly, a key intended forduplication (the master key) is copied on to an appropriately identifiedkey blank utilizing any number of different systems known in the art.The process of identifying an appropriate key blank to use when makingcopies of a key can be a difficult, tedious and time consuming affair.It is important that each master key be copied onto the proper key blankso as to prevent numerous adverse consequences caused by reproducing amaster key onto an inappropriate key blank. However, choosing thecorrect key blank can be difficult even for experts in the field.

There are hundreds, if not thousands, of key blanks, and many blanks arenot readily distinguished from others. Identifying the correct key blankfor use in duplication involves selecting a blank from hundreds or eventhousands of possibilities, where differences between key blanks may bevery subtle. These hard-to-notice subtleties significantly increase thelevel of difficulty for all operators of such key replication systems,both inexperienced trainees and experts alike.

Once a key blank is chosen, it goes through a cutting process. Thetypical cutting process simply traces the profile of the master key ontothe key blank, such that the key blank will exactly match (within theerror limits and accuracy of the tracing machine) the original masterkey. Normally, a mechanically linked cutting wheel actually cuts intothe key blank while it mimics the movement of the tracer as the tracermoves longitudinally along the profile of the master key. If theincorrect key blank is provided during this process, the key blank beingformed into the duplicate key may not possess the correct longitudinallength, thereby causing a failure. When this type of failure occurs, theentire process of selecting a key blank for replication and thenmechanically cutting the key must begin again. Worse still, if the blankhas the proper length but does not possess the appropriate thickness,contour, groove or other traits, the failure may not be discovered untilthe key is actually inserted into the lock.

Businesses that offer key cutting services are often times not staffedby experienced locksmiths. Instead, employees are usually trained to“eyeball” what is thought to be the correct blank and then cut aduplicate key. Such informal and imprecise key blank identificationinvariably increases the rate of failures for the duplication process.These failures often occur at the expense of the industry and to theextreme dismay of the key holder. Therefore, the industry would welcomean easy-to-use key blank identification system that increases theaccuracy and efficiency of key replication.

Not surprisingly, numerous attempts have been made to improveidentification systems and/or key replication systems. Many of theseimprovements include imaging systems designed to determine the properkey blank based on physical parameters of the key to be copied, such aslength, shape, and groove characteristics.

While many of these systems provide useful improvements for determininga proper key blank, they still suffer from various deficiencies.Specifically, many of these systems compare scanned data from a masterkey with data of known key blanks. However, in some instances thescanned key parameters and the key blank data are insufficient todetermine the proper key blank. In such cases, additional informationabout the master key and the key blank would be useful in narrowing thefield of prospective key blanks. Accordingly, an improved system andmethod for determining a key blank is needed.

SUMMARY

A key identification system is provided. The key identification systemcomprises a sensing device configured to determine information andcharacteristics of a master key, and a logic to analyze the informationand characteristics of the master key. The sensing device may beconfigured to capture information about the bittings of the master key.The logic analyzes information about the bittings and compares it withbitting characteristics of known key blanks to determine the likelihoodof a match between the master key and the known key blanks.

In an embodiment, the system configured to extract bitting informationmay comprise an imaging system, such as a camera or other imagingdevice. The camera may capture an image, such as a digital image, of thebittings of the master key to be analyzed by the logic.

DESCRIPTION OF THE DRAWINGS

Objects and advantages together with the operation of the invention maybe better understood by reference to the following detailed descriptiontaken in connection with the following illustrations, wherein:

FIG. 1. illustrates a master key.

FIG. 2. illustrates an embodiment of the key ID system.

FIG. 3 illustrates an example comparison chart between a TR47 master keyand TR47 key data.

FIG. 4 illustrates an example comparison chart between a KW1 master keyand KW1 key data.

FIG. 5 illustrates an example comparison chart between a KW1 master keyand SC1 key data.

FIG. 6 illustrates an example comparison chart between a KW1 master keyand AM3 key data.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to exemplary embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. It is to be understood that other embodiments may be utilizedand structural and functional changes may be made without departing fromthe respective scope of the present invention.

A system for identifying a key blank (“key ID system”) and method foridentifying a key blank are provided. The key ID system analyzes amaster key to be duplicated, such as a house key, car key or other key,and determines the appropriate key blank to be used. The system andmethod described herein may be used independently to determine a properkey blank, or may be used in conjunction with other systems to narrowthe field of prospective key blanks. Moreover, it will be understoodthat existing key identification systems may be modified or retrofittedto implement some or all features described herein.

With reference to FIG. 1, a master key 10 is depicted. The master key 10may include standard key features such as a head 16 and a blade 18. Theblade 18 may connect at one end to the head 16 with the tip 14 at theopposing end. The master key 10 may include teeth or bittings 12 cutinto the blade. The bittings 12 consist of notches cut in the blade 18to interface with the tumblers of a corresponding lock. The bittings 12must match up with the lock's unique tumbler configuration in order toactivate and turn the lock.

The key ID system may analyze the master key 10 to determine certainphysical characteristics of the key 10. Based on these characteristics,the key ID system may then determine the proper key blank to be used toduplicate the master key 10. For example, the key ID system may includea sensing device or system to extract bittings information from a masterkey 10. The sensing system may sense and capture parameters of thebittings 12. The sensing system may include any mechanical, electronicor optical sensors, sensors, imaging devices or other tools known in theart for extracting physical characteristics of a key or similar object.

In an embodiment, the sensing system for extracting bittings informationfrom the master key 10 includes an imaging system to scan and analyzethe physical characteristics of the master key 10. As is known in theart, the imaging system may be a laser imaging system, an opticalimaging system, a photo imaging system, or any other imaging systemknown in the art. The imaging system may scan the master key or capturean image of the master key to determine characteristics of the key thatare unique to a specific key blank. Further, it will be appreciated thatother known methods or devices, such as electrical, mechanical, oroptical sensors, may be used in place of or in conjunction with theimaging system to determine the traits and characteristics of the masterkey geometry.

In an embodiment illustrated in FIG. 2, the imaging system includes oneor more cameras 20 configured to capture an image, such as digitalimages, of the master key 10. The camera 20 may specifically bepositioned to capture an image of the blade 18 and bittings 12. Thecamera 20 may be positioned perpendicular to the blade 18.Alternatively, the camera 20 may positioned at an angle or at otherposition to capture the desired image

The imaging system may further include other components to aid incapturing images of the master key 10, such as one or more lights 24 andmirrors. The lights 24 may be positioned to enhance the clarity andquality of the image recorded by the imaging system. For example, thelight 24 may be positioned to provide backlighting for the key. Themirrors may be positioned to allow a camera in a first position torecord an image of the key from a second position. The mirrors mayfurther allow a single camera to record multiple images of the masterkey from different angles, thereby increasing the amount of informationrelated to the master key recorded by a single camera

As illustrated in FIG. 2, the image system may include one or morereflectors 26. The reflector 26 may be positioned to direct light to adesired location. For example, as shown in FIG. 2, a reflector may bepositioned underneath the key 10 and facing the light 24. The reflector26 may be angled, such as tilted upwards, to direct light from the light24 to the underside of the key 10, thereby providing backlighting of thekey 10. It will be appreciated, however, that the light 24 and reflector26 may be arranged in any configuration to optimize or clarify the imageof the key 10.

The key ID system may include a key holder 22 to hold the master key 10.The key holder may be any device capable of holding or supporting amaster key 10. For example, as shown in FIG. 2, the key holder 22 maycomprise a lower support and an upper door to close onto the key 10. Thekey holder may alternatively comprise a clamp, gripper, platform,suspension, or any other device configured to hold the master key 10.

As described in further detail below, the key ID system may analyzecharacteristics of the master key's teeth or bittings 12. Because thebittings 12 are configured to match up with the corresponding lock'sunique tumbler configuration, various characteristics of the bittings 12are often unique to certain types of key blanks. For example, certainkey manufacturers may use distinct bitting patterns, or a set of uniquebitting patterns, for their locks or for a group of locks. Additionally,certain types of keys, such as house keys or car keys, may use adifferent bittings configuration than other types of keys. By analyzingthe master key bittings 12 and comparing them to bitting configurationsused with known key blanks, the field of prospective matching key blanksmay be greatly reduced.

The key ID system may include a logic to analyze bitting characteristicinformation captured by the key ID system. As used herein, the term“logic” includes but is not limited to a software, a firmware, anexecutable program, a hardware or hard-wired circuit, or combinationsthereof. For example, based on a desired application or needs, a logicmay include a software controlled microprocessor, discrete logic like anapplication specific integrated circuit (ASIC), an analog circuit, adigital circuit, a programmed logic device, a memory device containinginstructions, or the like. Logic may include one or more gates,combinations of gates, or other circuit components. Logic may also befully embodied as software. Where multiple logics are described, it maybe possible to incorporate the multiple logics into one physical logic.Similarly, where a single logic is described, it may be possible todistribute that single logic between multiple physical logics.

The logic may be configured to determine a correlation or likelihood ofa match between a known key blank and the master key 10. For example,the logic may include a database to store key related information (“keydata”). The key data may include characteristics of known key blanks,such as length, shape, bitting information, size, shape and location ofkey grooves, and other geometric and physical characteristics of knownkey blanks. The database may be integral with the logic, incommunication with the logic, or remotely accessible to the logic. Thedatabase may associate key data with specific key blanks or with typesor groups of key blanks. For example, the database may associate keydata with specific key manufacturers or different types of keys such ashouse keys or car keys. The key ID system may access the database tocompare scanned characteristics of the master key with the stored keydata in the database. Key blanks that do not have characteristicsconsistent with those of the master key may be then ruled out aspossible matches for the key blank. The key ID system may scan themaster key 10 at one or more angles and compare the scanned data withstored key data.

In an embodiment, the database stores key data related to bittings usedwith known key blanks. Traditionally, key bittings are represented as anumeric bitting code that contains information as to how a key is to becut by a locksmith. Often the bitting code is a series of integers (e.g.372164) that may be translated or decoded from a key code chart orbitting code list. However, not all the information in the bitting codeis necessary in order to determine unique properties of the bittings.Therefore, the database may store data related to known key bittingpatterns other than numeric bitting codes. For example, the database maystore measurements of bitting geometries used with known key blanks.

Stored bitting geometries may include bitting spacings, notch depths,blade width, and bitting flat width. Spacing data may relate to thelocation or spacing between of each bitting notch along the length ofthe key blade 18. Spacing data may be measured from the center of eachnotch to a specific reference point, such as the tip 14 or shoulder ofthe blade 18. Depth data may relate to the depth of each bitting notchand may be measured as the distance between a reference edge, such asthe back side or center line of the blade 18, and the notch surface.Blade width may relate to the width of the blade surface to be cut.Bitting flat width may relate to the width of each notch surface and maybe measured as the distance across the bottom of the notch.

In an embodiment, the logic may determine bitting parameters of themaster key 10 by analyzing an image captured by an imaging system. Thebitting parameters may be compared to bitting data in the database todetermine if the master key 10 matches a key blank or blanks in thedatabase. As shown in FIGS. 3-6, bitting parameters of the master key,such as spacing and depth, may be analyzed at various preselectedpoints, such as at the bitting notches. The master key bittingparameters may then be compared to bitting data in the database. If thebitting parameters of the master key match the bitting data of a keyblank in the database, then that key blank may be appropriate forduplicating the master key. For example, if each bitting depth of amaster key 10 is very close to an allowable bitting depth for a givenkey blank, then the key blank may be a match. Likewise, if the bittingflat width and spacing of the bittings of a master key 10 are close toallowable bitting flat widths and spacings for a given key blank, thenthe key blank may be a match. However, if the bitting data of the masterkey is not close to allowable data for a given key blank, then the givenkey blank or blanks may be ruled out as a possible match.

The database may associate bitting data with various key-relatedidentifiers. For example, while bitting data may be directly associatedwith specific key blanks, it may also be associated with groups of keys,such as keys made by a specific key manufacturer or certain types ofkeys. Accordingly, large groups of potential key blanks may be ruled outif a bitting parameter of the master key does not match a bittingparameter shared by the group of keys.

The bitting positions can be analyzed in any number of methods. Oneembodiment includes first determining the pattern of the unknown subjectkey. Each stored pattern may then be tested against the subject key. Thetest may involve checking each of the known spacing positions for thestored pattern and seeing if there is a bitting at that position. Toaccomplish this, the logic may analyze or measure the slope or anglewith respect to the length of the blade 18 of the master key patternnear the sample position and determining if there is a “flat” in thatposition. A flat could be defined as a small segment of the pattern(0.020″ wide for example) with a slope or angle that is close to 0degrees, (less than 17 degrees for example) that is either centered,just left or right of, the target spacing position. If a flat isidentified, then the depth of the flat can also be identified from thesubject key pattern relative to the reference axis.

To account for reasonable variances in the master key, the key ID systemmay set tolerance ranges for each bitting parameter measurement. Inorder for a key blank to match a master key, the comparison values mustfall within the predetermined tolerance range. For example, asillustrated in the test results window of FIGS. 3-6, the tolerance rangefor bitting depth may be set to plus or minus six thousandths of aninch. In order for the master key to match a key blank, each depthmeasurement comparison must fall within this range. As shown in FIGS. 3and 4, the comparison values are all between −1 and +1, indicating amatch between the master key and the tested key blank or blanks FIGS. 5and 6, however, illustrate comparison values of greater than 6,indicating that the master key does not match the tested key blank orblanks. The pass/fail limits (tolerance range) could be based on a setrange, a set percentage of the depth offsets of the target key, or someother parameter. The limits may be set the same for all keys or may beindividualized on a key-by-key basis.

To account for positional variation inherent to the subject keys and/orthe inspection system, the pattern matching algorithms may be repeatedwhile shifting the data by small increments (0.020″ for example) ineither or both directions. For example, if a key blank was slightlymiscut and the spacing was shifted from the nominal position, the searchmay fail at the nominal position but may identify the pattern shiftedslightly over from the nominal position.

The spacing and depth evaluations may be measured using a scoring systemof 0 to 100%, where 0 is considered to be an impossible match and 100 isa perfect match. The total bitting score is then the product of thecombined spacing and depth scores.

The logic may compare the bittings of a master key 10 to key datarelated to a key blank in the database and evaluate a series of presetspacing point for the given key blank. For example, the geometry of themaster key 10 may be analyzed at each spacing point. A score may begiven to each spacing point based on the flatness of the bitting 12 atthe spacing point and a measurement of the variation or slope of thebitting 12 relative to the database depths. The relationships betweenangles can be varied to achieve optimal results. The flatter the areanear the spacing point, the higher the score. For example, zero degrees(or flat) might represent a score of 100 and 45 degrees might represent0. Similarly, the logic may analyze the depth of the blade at eachspacing point give a score to the spacing point based on the variationfrom one of the valid depths for the given key blank stored in thedatabase. For example, no variation might represent a score of 100 and2× the differences between depths might represent a score of 0.

The logic may compute this evaluation for each of the spacing points andthen compute a total by averaging all the points. This entire processmay be repeated with a slight shift towards the head 16 of the key 10and again with a shift towards the tip 14 of the key 10. This willcompensate for a key 10 that has a slight spacing shift. The best of thethree totals are used in the final results for the bitting evaluation.

The logic may determine the centers of each of the flats on the bittings12 of the master key 10. Because the center of a flat that is on thepeak of a bitting may be skewed due to the depth of the bitting on theleft and right, the logic may ignore peaks. The logic may also ignoreridges because the center of flats that are on ridges may be skewed dueto the depth and height of the bittings 12 on either side. However,flats that are located in “valleys,” or between bittings of lesserdepth, are often properly centered regardless of what is on either side.For each identified valley, the logic may compare the nearest databasespacing position and a score is given. A total spacing score is thencomputed based on the average score for each of the valleys.

It will be appreciated that the database is not limited to bittingsdata. In addition to bittings data, the database may store informationrelated to other identifying parameters of the key. The key ID systemmay utilize other key parameters, in combination with bittingsinformation, to narrow the field of possible key blanks.

The key ID system as described may be used in conjunction with otherknown key identification systems. For example, the key ID system may beused in conjunction with user interface identification systems, such asthe object identification system disclosed in U.S. Publication No.2004/0095380 and the key duplication system disclosed in U.S.Publication No. 2007/0224008, each of which are hereby incorporated byreference in their entirety.

The invention has been described above and, obviously, modifications andalternations will occur to others upon a reading and understanding ofthis specification. The claims as follows are intended to include allmodifications and alterations insofar as they come within the scope ofthe claims or the equivalent thereof.

Having thus described the invention, we claim:
 1. A key identification system comprising: a sensing system configured to extract bitting information from a master key; a logic configured to analyze said bitting information to determine characteristics of said bittings of said master key and further to compare said characteristics of said bittings with bitting characteristics of known key blanks to determine the likelihood of a match between said master key and a known key blank; and wherein said bitting information includes at least one of the depth of a bitting, the width of a bitting, and the location of a bitting along a blade of said master key.
 2. The key identification system of claim 1, wherein said logic includes a database containing data related to bitting characteristics of known key blanks.
 3. The key identification system of claim 1, wherein said sensing system. comprises an imaging system.
 4. The key identification system of claim 3, wherein said imaging system is configured to capture an image of the bittings of said master key.
 5. The key identification system. of claim 3, wherein said imaging system includes a camera.
 6. The key identification system of claim 5, wherein said camera is positioned. perpendicular to the blade of said master key.
 7. The key identification system of claim 3, wherein said imaging system. includes a light.
 8. The key identification system of claim 4, wherein said captured image is a digital image.
 9. The key identification system of claim 1 further comprising a key holder to hold said master key.
 10. The key identification system of claim 9, wherein said key holder comprises a support and an upper door.
 11. The key identification system of claim 2, wherein said data related to bitting characteristics of known key blanks includes a set of depths at given blade spacing points associated with a given key blank.
 12. The key identification system of claim 2, wherein said data related to bitting characteristics of known key blanks includes a set of bitting flat widths at given blade spacing points associated with a given key blank.
 13. The key identification system of claim 2, wherein said data related to bitting characteristics of known key blanks includes a set of bitting centers associated with a given key blank.
 14. The key identification system of claim 11 wherein said logic compares the depth of the master key bitting at each spacing point to said set of depths for said given key blank.
 15. The key identification system of claim 14 wherein said logic computes a score for said given key blank based on the comparison between the depths of said master key at each spacing point and said set of depths for said given key blank.
 16. The key identification system of claim 12 wherein said logic compares the bitting flat widths of the master key bitting at each spacing point to said set of bitting flat widths for said given key blank.
 17. The key identification system of claim 16 wherein said logic computes a score for said given key blank based on the comparison between the bitting flat widths of said master key at each spacing point and said set of bitting flat widths for said given key blank.
 18. The key identification system of claim 13 wherein said logic compares the bitting centers of the master key bitting to said set of bitting centers for said given key blank.
 19. The key identification system of claim 18 wherein said logic computes a score for said given key blank based on the comparison between the bitting centers of said master key and said set of bitting centers for said given key blank.
 20. The key identification system of claim 2, wherein said logic analyzes one of a bitting depth, a bitting flat width, and a bitting center of said master key at a blade spacing point shifted from said blade spacing point associated with a given key blank. 